To understand the deposition and transport of PAHs in southern China, a measurement campaign was conducted at a high-elevation site (the summit of Mount Heng, 1269 m A.S.L.) from April 4 to May 31, 2009, and a total of 39 total suspended particulate samples were collected for measurement of PAH concentrations. (hindawi.com)

Good correlations were found between individual PAHs and meteorological parameters such as atmospheric pressure, relative humidity, and ambient temperature. (hindawi.com)

The backward trajectory analysis suggested that particulate samples measured at the Mount Heng region were predominantly associated with the air masses from southern China, while the air masses transported over northern and northwestern China had relative higher PAHs concentrations. (hindawi.com)

Nowadays in Chinese villages, rapid economic development and urbanization continue to consume large amounts of fossil fuel and biomass each year and thus produce more PAHs, which could enter surface water through atmospheric fallout. (hindawi.com)

Project referenceProject:Pilot project in the Bangkok region of ThailandProject period2000Nature of task: investigation of the air pollution and the connection between ambient air and aquatic plant concentrations of PAHs in the Bangkok region of Thailand contribution of traffic to atmospheric and plant concentrations of PAH SummaryThe individual PAH compounds phenanthrene, 1-methylphenanthrene, fluoranthene and pyrene were predominant in all samples indicating that traffic probably contributed to the high. (environmental-expert.com)

According to Clar's rule (formulated by Erich Clar in 1964) for PAHs the resonance structure with the largest number of disjoint aromatic п-sextets-i.e. benzene-like moieties-is the most important for the characterization of the properties. (wikipedia.org)

Substantially higher outdoor air, soil, and water concentrations of PAHs have been measured in Asia, Africa, and Latin America than in Europe, Australia, and the U.S./Canada. (wikipedia.org)

Other compounds believed to be indicated by the data and associated models include ammonia, polyynes, amines, ethylenimine, deuterium hydride, allene, 1,3 butadiene and any number of more complex chemicals in lower concentrations, as well as carbon dioxide and limited quantities of water vapour Due to its distance from the Sun, Titan is much colder than Earth. (wikipedia.org)

Use of organic tracers has become more common as measurement quality has improved, costs have decreased, and compounds that were historically good tracers, such as lead, have decreased in ambient concentrations due to various factors including government regulation. (wikipedia.org)

During a study involving the concentration of heavy metals, pesticides, and semi-volatile organic compounds in stream sediments from the Schuylkill River within the Valley Forge National Historical Park, the USGS used the ERL and ERM to determine locations that could potentially pose a threat to living organisms. (wikipedia.org)

Mussel Watch monitors the concentration of contaminants in bivalves (mussels and oysters) and sediments in the coastal waters of the U.S., including the Great Lakes, to monitor bivalve health and by extension the health of their local and regional environment. (wikipedia.org)

not verified in body] Even so, diesel exhausts continue to contain an array of inorganic and organic pollutants, in various classes, and in varying concentrations (see below), depending on fuel composition and engine running conditions. (wikipedia.org)

The higher values occurred during periods of elevated O3 and PAN concentrations, suggesting there may be an artifact effect during particulate collection associated with one or both of these two types of filters. (ca.gov)

Presence of such smoke, soot, and/or brown oily deposits during a fire indicates a possible hazardous situation, as the atmosphere may be saturated with combustible pyrolysis products with concentration above the upper flammability limit, and sudden inrush of air can cause flashover or backdraft. (wikipedia.org)

As the Sun's ultraviolet output decreases, the haze in Titan's upper atmosphere will be depleted, lessening the anti-greenhouse effect on its surface and enabling the greenhouse effect created by atmospheric methane to play a far greater role. (wikipedia.org)

Examples of some results of preferential emissions from sources include hopanes, polycyclic aromatic hydrocarbons and steranes from different types of mobile sources, retene and methoxyphenols from wood smoke, odd n-alkanes and even n-alkanoic acids from vegetative detritus, cholesterol and the C16 and C18 n-alkanoic acids from cooking, and lighter n-alkanes from brake wear. (wikipedia.org)

Following here is a summary of how the ERL/ERM guidelines are used by the National Oceanic and Atmospheric Administration, United States Geological Survey (USGS), and the United States Environmental Protection Agency (EPA). (wikipedia.org)

These predicted levels suggest that N205 may be important as an atmospheric constituent, both in nitration reactions of PAH and in the nighttime formation of nitric acid, a major component of acidic deposition. (ca.gov)

For analysis of atmospheric processes in the urban environment, the microscale meteorological and dispersion model M2UE is suggested, which takes into account a complex character of aerodynamics in non-uniform urban relief. (environmental-expert.com)

Future UK PCB air concentrations will presumably therefore be influenced (controlled) by the rate of desorption and outgassing, as soil and air concentrations move towards a condition of equilibrium partitioning. (lancs.ac.uk)

Oil spills provided perfect opportunities for scientists to examine the in situ effects of crude oil exposure to marine ecosystems, and collaborative efforts between the National Oceanic and Atmospheric Administration (NOAA) and the United States Coast Guard resulted in improved response efforts and detailed research on oil pollution's effects. (wikipedia.org)

Across the United States, NOAA has used these guidelines in regional surveys to determine the degree of contamination relative to other areas, and to identify if the concentration of a chemical exceeded guidelines, indicating a possible adverse effect. (wikipedia.org)

The National Oceanic and Atmospheric Administration (NOAA) National Status and Trends (NS&T) Mussel Watch Program is a contaminant monitoring program that started in 1986. (wikipedia.org)

The numerical values are incorporated in sediment quality guidelines (SQGs) that were developed by Long and Morgan for the National Oceanic and Atmospheric Administration (NOAA) National Status & Trends program as informal tools to evaluate whether a concentration of a contaminant in sediment might have toxicological effects. (wikipedia.org)

The USGS has also integrated ERL and ERM values into an Alert Range Table, a table that provides ranges of contaminant concentrations that predict the likelihood of adverse effects occurring in benthic organisms for the Lake Pontchartrain Basin in Louisiana. (wikipedia.org)

2-Nitrofluoranthene was the most abundant nitro-PAH, accounting for 54% of the total nitro-PAH concentration, followed by 9-nitroanthracene, 3-nitrophenanthrene and 7-nitrobenz(a)anthracene, about 15%, 16% and 10%, respectively. (environmental-expert.com)